The shooter who has fired at the Pentagon, the National Museum of the Marine Corps in Triangle, Va., and the Marine recruiting station in Chantilly, Va., in recent weeks may be a Marine or someone with a grievance against the U.S. Marine Corps, federal officials said Friday. FBI officials released a limited profile of the shooter and said all the shots came from the same gun and probably from the same person. Authorities think Marine Corps locations are being singled out, and security has been stepped up for Sunday's Marine Corps marathon.

Elsewhere

Paris: French workers ended their strikes at all oil refineries and at strategic fuel terminals following weeks of protests over President Nicolas Sarkozy's plan to raise the retirement age from 60 to 62, unions and French officials said Friday.

Vienna: Iran offered on Friday to negotiate with six world powers about its disputed nuclear program in a new bid to end growing concern that it could be used to produce weapons.

Seoul, South Korea: North Korean troops fired shots Friday in the direction of a South Korean military unit across the heavily armed border, prompting return fire, South Korean officials said. No injuries were reported.

Reno, Nev.: A gunman who police said was about to be fired surrendered Friday after shooting and wounding three co-workers at a Walmart store in a possible retaliation attack.

Boulder, Colo.: Two wildfires on Friday led to the evacuations of the homes of 1,700 people in an area where dozens of houses burned last month.